The objective of this study is to test the hypothesis that short-term, educational intervention can significantly and cost-effectively improve the ability of primary care physicians to identify and appropriately refer patients with diabetic retinopathy. This objective is consistent with the mandates of the National Eye Health Education Program. In order to test this hypothesis, we will perform a multi-center investigation at Georgetown University, Duke University, and the University of Southern California to compare the effect of five educational strategies on the diagnostic accuracy, clinical knowledge, and practice patterns of groups of primary-care physicians with regard to the detection and management of diabetic retinopathy. We will develop standardized educational programs on the pathophysiology, ophthalmoscopic identification, current ophthalmologic management, and appropriate referral of patients with diabetic retinopathy. These programs will be comprised of combinations of the following elements: 1) A programmed Independent Study course 2) A lecture and hands-on instruction program that incorporates examination of model eyes that simulate those of patients with diabetic retinopathy 3) A lecture and hands-on instruction program that incorporates examination of live patients with diabetic retinopathy 4) A lecture and hands-on instruction program that incorporates examination of live patients with diabetic retinopathy as well as practice with the model eye 5)The lecture and hands-on instruction program described in option #4 above, delivered both at baseline and at 6 months We aim to measure the baseline and post-intervention diagnostic skills and management ability of participating primary care physicians in evaluating patients at risk for diabetic retinopathy. Because the five trial interventions have significantly different cost implications, we will further evaluate the potential cost-effectiveness of each in preventing the needless loss of sight years in the American population.